Metal buildings are popular due to the relatively quick construction and low cost, as well as low maintenance. However, metal components of these buildings have high thermal conductivity, and thus it is difficult to efficiently and effectively control temperatures within such metal buildings. Heating and cooling costs can be relatively high.
Conventional ceiling insulation in metal buildings involves placing a layer of insulating material over the top of the roof purlins, with the roof deck then being attached over the insulation to the purlins. The roof deck squeezes the insulation above each purlin thereby reducing the R-value and increasing energy loss. The insulation is installed from the outside of the building, and involves relatively costly labor which can also be dangerous and difficult in windy or wet conditions.
Applicant's patent U.S. Pat. No. 6,330,779 overcame many of the problems associated with conventional insulated ceilings for metal buildings by attaching a substantially rigid insulated sheet to the bottom flange of the purlins and then filling the space between the insulation board and the roofing deck with insulation. However, the insulation board was attached to the purlins using penetrating fasteners, such as self tapping screws. This method of attaching the insulation board to the purlin is time consuming and therefore costly. Also, the metal screws provide thermal conductivity through the metal purlins and metal roof decking, thereby reducing the R-value and increasing energy costs.
Therefore, a primary objective of the present invention is the provision of an improved insulated ceiling for a metal building with minimized thermal conductivity.
Another objective of the present invention is the provision of a purlin clip for quickly and easily attaching insulation board to purlins in a metal roof structure.
Another objective of the present invention is the provision of an insulated ceiling in a metal roof which attaches insulation board to the metal purlins without the use of penetrating fasteners.
A further objective of the present invention is the provision of a method of building an insulated ceiling which is inexpensive yet energy efficient.
A further objective of the present invention is the provision of a method of insulating a metal roof inside of the building after the roof deck has been installed.
These and other objectives will become apparent from the following description of the invention.